System for attaching a firearm accessory to a firearm site base

ABSTRACT

A system for attaching a firearm accessory to a sight base including a first bore in the sight base, a second bore in the accessory body and a bushing inserted into the second bore. A bushing is inserted into the second bore and is held in place with one or more protrusions located on the sight base near the first bore and/or a screw inserted into a bore in the bushing. The bushing allows the accessory body to rotate in a plane that is perpendicular to the first and second bores. A screw inserted into a third bore that communicates with the second bore allows a screw to engage the exterior surface of the bushing featuring grooves that define positions to which the accessory body can be rotated. The accessory body&#39;s rotation can also be stopped using a groove on the accessory body that is engaged by another protrusion featured by the sight base.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application claims the benefit of priority to U.S. Provisional Application No. 62/445,777 filed on Jan. 13, 2017. The content of U.S. Provisional Application No. 62/445,777 filed on Jan. 13, 2017 is incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION (a) Field of the Invention

The present invention relates to a device that mounts to a sight block or sight base for a firearm that allows the shooter the option of attaching firearm accessories to the sights or at the position of the sites that are already present or have been added to a firearm. More specifically, preferred embodiments of the device or system physically attach to the front and rear sights of a long gun such as an AR-15 rifle. The presently disclosed embodiments are intended to be used with any rifle or other long gun and specific reference is made to the AR-15 platform for illustrative purposes only.

(b) Background Art

Canted sights have been available for firearms such as the AR-15 for some time, and while effective, they tend to be difficult to operate. In addition, since most canted sights are side mounted on the rail system or handguard, they are susceptible to damage, etc.

The present device provides alternative sighting options for an operator in situations that require canting or rotation of the firearm or the use of a firearm accessory. Such situations may include close quarters combat or situations in which the top mounted optics are damaged or inoperable. In event of optic failure, the operator can easily engage the mechanism and fire the firearm in a canted position. In addition, since other firearm accessories can be part of or attached to the disclosed device or system, the device enables an operator to use an accessory in conjunction with the top mounted optics on a firearm.

BRIEF SUMMARY OF THE INVENTION

Early embodiments of the device include a bracket capable of receiving and attaching to the sight block or mounted sights normally present on most if not all modern rifles. More specifically, these embodiments of the device include a bracket that is configured to be attached to an existing sight block or sight base, i.e., the structure attached to the firearm that contains the front sight. Alternately the bracket and the front sight base could be one structure that is attached directly to the firearm in the same manner that front sights are typically mounted to long guns.

The bracket is configured to securely hold any number of accessories commonly used with firearms including, but not limited to iron sights, red dot sights, other optic devices, flashlights and other tactical lights, cameras, recording devices such as cameras and GPS modules and tracking systems.

In preferred embodiments, the mounting bracket has a surface containing female engagement divots that will allow the accessory to interlock with the bracket and thus the front sight block or sight base mount. The block containing or encompassing the accessory (the accessory block or body) contains a corresponding (male) spring assisted ball end set screw that is shaped and positioned to engage with the female engagement divots. A bushing in the accessory block, for example, inserted into a bore in the accessory body, allows the accessory attached to the bracket to rotate in a circular plane, i.e., the accessory can be rotated in a plane or direction that is perpendicular to the longitudinal axis of the barrel of the firearm. The locations of the divots allow the accessory block to be turned to predetermined locations at an angle to the bracket and thus the axis of the barrel.

In addition, other preferred embodiments will not include the divots, which represent positions at which the rotation of the accessory is stopped, i.e., the user turns the accessory clockwise or counterclockwise so that the set screw can engage a different divot. Eliminating the divots and just providing a groove for the set screw to engage with allows the user to fine tune the position of the accessory and place it at virtually any angle to the rest of the firearm.

Other means of attaching the accessory to the bracket include a sliding cam, a notched dial or other structural equivalents. As mentioned above, the set screw has pressure or force applied to it by a spring positioned to do so. That helps the set screw engage with the female divots and/or groove on the bracket. Alternately, the divots or groove could be located on the accessory and the set screw could be featured by the bracket.

The mounting bracket can be constructed of metal, plastic or other materials commonly used for firearm accessories and parts, and attaches onto the existing post mount frame or the front sight as shown in the figures. In the preferred embodiments, the bracket is mounted to an existing front sight block or sight base through the use of at least one set screw inserted through the side walls of the bracket. Other embodiments include a modification of the existing post mount frame or front sight block to include a threaded hole or holes on the front surface of post mount frame or sight block whereby the bracket may be securely attached to the sight block or sight base. In such embodiments, the need for the side walls with set screws is eliminated. As a skilled artisan could appreciate, there is no specific need to make each of these structures a separate piece, i.e., the sight block, accessory block and bracket could comprise one or even two or more separate structures that engage with each other. It is these embodiments that are described in more detail below in reference of the figures. Embodiments in which the sight base is modified to engage with the accessory body directly, without the use of a bracket represent the inventor's anticipated best mode of practicing the invention with the embodiments using the bracket being intended to be used with existing, unmodified sight bases.

The front sight accessory will be available in multiple configurations such as, but not limited to, single post or multiple post. Said posts are made of commonly used sight materials such as but not limited to metal, plastic, fiber optic, or tritium. A skilled artisan can appreciate that the rear sight mounting block or sight base can also be equipped with the same structures to produce a rear sight with the complementary structures at the rear of the firearm. Certain accessories will require the rear mounted bracket, attached to the rear sight; for example, canted iron sights will require a sight accessory to be mounted to both the front and rear sights.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1A is a cross sectional view of a sight base according to the present invention;

FIG. 1B is a front plan view of the same sight base;

FIG. 1C is a cross section view of the same sight base;

FIG. 1D is a close up view of the cutaway portion of FIG. 1C;

FIG. 2A is a front view of an accessory according to the present invention;

FIG. 2B is a cross section view of the same accessory;

FIG. 3A is a cross sectional view of the bushing used in the present invention;

FIG. 3B is a front plan view of the same bushing;

FIG. 3C is a close up view of the same bushing;

FIG. 4A shows a top plan view of the bracket used in certain embodiments of the present invention;

FIG. 4B shows a front plan view of the same bracket;

FIG. 5 shows an exploded view of the index screw used in the third bore; and

FIG. 6 is a cross section of the same screw.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1A through 1D show a modified sight base 10 for an AR-15. The sight base 10 has a body 11 that contains within it or features a bore 12. This bore 12 is hereinafter referred to as the first bore 12. In preferred embodiments, this first bore 12 features an interior surface 12 a featuring threads. FIGS. 1A through 1D also show the sight base 10 featuring the first bore 12. These figures also show two protrusions. The first protrusion 13 is closer in proximity to the first bore 12 than the second protrusion 14. The locations of these protrusions are not paramount in that they can function the same way if they are located on different parts of the sight base 10. They need to be positioned such that they can interact with structures on the accessory 15.

FIGS. 2A and 2B show an accessory 15 or accessory block that is configured to attach to a site base 10. The accessory has a body 15 featuring at least one bore—the second bore 16 that traverses the entire accessory body 15 from a first side 15 a of the accessory body 15 to an opposing second side 15 b of the same accessory body 15. In addition, FIG. 1B shows a third bore 17 that in this embodiment is located beneath the second bore 16. This third bore 17 traverses the exterior of the accessory body 15 and communicates with the second bore 16 in the accessory body 15. The third bore 17 also features a threaded interior surface 17 a. FIG. 1B goes on to show a bushing 18 inserted into the second bore 16.

FIGS. 3A through 3C show the bushing 18 that in inserted into the second bore 16 of the accessory body 15. The bushing has an interior surface 20 and an exterior surface 21. In preferred embodiments, the exterior surface 21 is machined to feature grooves 22. In other embodiments, the grooves 22 can be simple divots or cavities into which another object, like, such as a screw, can fit. In still other embodiments, the exterior surface 21 of the bushing 18 can feature a combination of grooves 22 and cavities. The bushing 18 also features a fourth bore 23. This bore can feature threads, but it is generally not necessary. Furthermore, FIGS. 3B and 3C show a cavity 19 featured on the bushing 18. This cavity 19 is complementary (shaped, sized and positioned to engage) the first protrusion 13 located on the sight base 10. The cavity 19 and the first protrusion 13 can be reversed, i.e., the sight base 10 could feature a cavity 19 complementary to the first protrusion 13 on the bushing 18.

FIGS. 4A and 4B show another embodiment of the same system described above. In this embodiment, the accessory 15 attaches to a bracket 24 that features structures that are very similar to those featured by the sight base 10 above. This embodiment is meant to be used on firearms that do not have a modified sight base 10 as described above. Rather than trying to remove the sight base 10 from and existing firearm—a task that can be rather difficult depending on the firearm, the bracket 24 can be used to attach the accessory 15 to a standard sight base 10. Similar to the sight base 10 described above, the bracket 24 has a threaded bore 25 and features a first protrusion 13 and a second protrusion 14. In addition, the bracket has one or more screw holes 26 that traverse the interior and exterior of the bracket 24. When screws are inserted in these screw holes 26, they attach the bracket to the sight base 10.

FIGS. 5 and 6 show an index or set screw 27 that inserts into the threaded interior surface 17 a of the third bore 17 located on the accessory body 15. This screw 27 has a ball shaped head 27 a, external threads 27 c that are complementary to the threaded interior surface 17 a of the third bore 17. In addition, this screw 27 features a spring 27 b that applies force to the ball-shaped head 27 a thereby pushing it outward and away from the rest of the screw 27. This screw 27, when inserted into the third bore 17, pushes the ball-shaped head 27 a outward to the point that it contacts the exterior surface 21 of the bushing 18.

The operation of this system is as follows. In preferred embodiments the accessory body 15 is attached to the sight base 10 such that the accessory body 15 can rotate around the bushing 18 inserted into the second bore 16 while the bushing 18 is held in place. The first protrusion 13 engages with a female divot 19 located on the bushing 18 adjacent to the fourth bore 23. As a result, the bushing 18 is held stationary while the rest of the accessory body 15 can be rotated around the bushing 18 in a plane that is perpendicular to the longitudinal axis of the fourth bore 23. Alternately, the bushing 18 can be made such that it features a flattened surface that engages with a shelf (not shown) in the first bore 12 thereby preventing the bushing 18 from rotating. In preferred embodiments, the rotation of the accessory body 15 can be limited such that the accessory body 15 can only rotate to certain predefined stopping positions. This can be accomplished a number of ways, but in preferred embodiments, there is a groove 15 c located adjacent to the second bore 16 on the opposing second surface 15 b. This groove 15 c is complementary to the second protrusion 14 featured by the sight base 10, i.e., the second protrusion 14 fits into this groove 15 c. The groove 15 c is curved such that the second protrusion 14 travels through the groove 15 c as the accessory body 15 rotates around the bushing 18. The sight base 10 is attached of the accessory body 15 in preferred embodiments, but inserting a screw (not shown) into and through the second bore 16 and into the first bore 12. The threads on the screw engage with the threaded interior surface 12 a of the first bore 12 and can engage with similar threads if they are featured inside the fourth bore 23 but, as mentioned above, that is not necessary to attach the sight base 10 and accessory body 15.

In embodiments that use the bracket 24, the first bore 12 is located on the bracket 24 rather than the sight base 10. The accessory body 15 attaches to the bracket 24 through the use of a screw (not shown) that is inserted into the and through the fourth bore 23 in the bushing 18 that is inserted into the second bore 16 of the accessory body 15. As discussed above, the bracket 24 features screw holes 26 such that screws can be used to attach the bracket 24 to a standard, unmodified sight base 10. Other embodiments can feature a sight base 10 featuring screw holes that serve the same purpose.

In the preceding description, terms such as horizontal, upright, vertical, above, below, beneath, and the like, are used solely for the purpose of clarity in illustrating the invention, and should not be taken as words of limitation. The drawings are for the purpose of illustrating the invention and are not intended to be to scale.

The advantages of the current system are many including the ability to provide multiple sighting options on a single rifle and the ability to customize the positioning of accessories in a way not seen heretofore. In addition, attaching these accessories to the sight blocks greatly influences the accuracy of the accessory in use.

Reference throughout the specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussion of the features and advantages, and similar language, throughout the specification may, but do not necessarily, refer to the same embodiment.

Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.

It is understood that the above described embodiments are only illustrative of the application of the principles of the present invention. The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiment, including the best mode, is to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, if any, in conjunction with the foregoing description.

While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The invention should therefore not be limited by the above described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention. 

I claim:
 1. A system for attaching a firearm accessory to a firearm comprising: a sight base; wherein said sight base has a body featuring a first bore; wherein said first bore has an interior surface featuring threads; and wherein said sight base also features a first protrusion adjacent to the first bore; an accessory with a body featuring a second bore and a third bore; wherein the second bore traverses an exterior of the accessory body and communicates with the second bore; said second bore having a first end and a second end; said third bore traverses the exterior of the accessory body and communicates with the second bore; said third bore featuring an inner surface with threads; a cavity and/or groove located on the accessory body adjacent to the second bore; wherein said first protrusion featured by the sight base is complementary to and engaged with the cavity and/or groove on the accessory body; a bushing inserted into the second bore; said bushing featuring an interior surface and an exterior surface and a fourth bore; said exterior surface featuring one or more grooves and/or one or more divots; an index screw featuring threads complementary to the threads featured by the third bore; wherein when the index screw is inserted into the third bore it engages the exterior surface of the bushing inserted into the second bore; a set screw featuring threads that are complementary to the threads on the interior surface of the first bore; said set screw being positioned such that it passes into and through the second bore into the first bore to engage with the threads featured by the interior surface of the first bore; wherein said set screw extends through the first and second bores, thereby engaging the accessory body and the sight base body thereby allowing the accessory body to rotate in a plane that is perpendicular to the longitudinal axis of the fourth bore while the bushing is held in place and prevented from rotating.
 2. The system of claim 1 further comprising an exterior surface on the bushing that features one or more grooves and/or one or more divots and said third bore features an inner surface with threads; and an index screw featuring threads complementary to the threads featured by the third bore; wherein when the index screw is inserted into the third bore it engages the exterior surface of the bushing inserted into the second bore.
 3. The system of claim 2 further comprising: a second protrusion featured on the sight base adjacent to the first bore; a cavity featured on the bushing; wherein the second protrusion is complementary to the cavity featured by the bushing and engages the cavity thereby securing the bushing and preventing it from rotating.
 4. A system for attaching a firearm accessory to a firearm comprising: a sight base with a body featuring a first bore; an accessory with a body featuring a second bore; wherein the second bore traverses an interior and an exterior of the accessory body; a bushing inserted into the second bore; a set screw that extends through the first and second bores, thereby engaging the accessory body and the sight base body and allowing the accessory body to rotate around the bushing in a plane that is perpendicular to the longitudinal axis of the second bore.
 5. The system of claim 4 further comprising: an exterior surface on the bushing that features one or more grooves and/or one or more divots and a third bore with an inner threaded surface featured by the accessory body; an index screw featuring threads complementary to the threads featured by the third bore; wherein when the index screw is inserted into the third bore it engages the exterior surface of the bushing inserted into the second bore.
 6. The system of claim 5 wherein the index screw features a ball shaped head and the screw is pushed towards the second bore by a spring positioned to apply a pushing force.
 7. The system of claim 6 further comprising a first protrusion on the body of the sight base; said first protrusion being positioned adjacent to the first bore; and a groove featured by the accessory body adjacent to the second bore that is complementary to the first protrusion; whereby the protrusion engages the groove and stops the rotation of the accessory body at certain predetermined positions.
 8. The system of claim 4 wherein the first bore features and inner surface with threads and the screw features threads complementary to the threads in the first bore and the accessory body. 